C 颠倒句子中的单词

我目前正在学习K.N.King的C编程：一种现代方法。我已经读完了第8章（数组）的内容，我很想继续读第9章，但我还没有解决每章末尾的所谓“编程项目”。不幸的是，14号。。。烦死我了

编写一个程序，将句子中的单词颠倒过来

提示：使用循环逐个读取字符并将其存储在一维字符数组中。让循环在句点、问号或感叹号（“终止字符”）处停止，该句点保存在单独的char变量中。然后使用第二个循环在数组中向后搜索最后一个单词的开头。打印最后一个单词，然后向后搜索下一个单词。重复此操作，直到到达数组的开头。最后，打印终止字符

*/
#include<stdio.h>

int main()
{
int ch;
char sentence[200]; //hard set a limit of 200 character sentence
char word[10] = {'\0','\0','\0','\0','\0','\0','\0','\0','\0'}; //hard set limit of 10 character words
int i = 0; //character position in input
int w = 9; //character position in word
char terminator = '\0';
printf("Enter a sentence:");
   while  ( (ch=getchar()) != '\n' )
       {
       if ( ch == '.' || ch == '?' || ch == '!')
          terminator = ch;
       else
         {
         sentence[i] = ch;
         i++;
         }
//       printf("%d",i);
       }
       sentence[i] = '\0';//set last character to null


    int x;
    for ( x=i ; x >= 0 ; x-- )
        {
           if ( sentence[x] == ' ' )
           {
            printf(" ");//print the space followed by what is in the word buffer/array
//          printf("word length %d ",w);
            printf("%c",word[0]); //probably should have a for loop here
            printf("%c",word[1]);
            printf("%c",word[2]);
            printf("%c",word[3]);
            printf("%c",word[4]);
            printf("%c",word[5]);
            printf("%c",word[6]);
            printf("%c",word[7]);
            printf("%c",word[8]);
            printf("%c",word[9]);
            w = 9 ;
            word[0] = '\0'; //fill the word buffer/array with null
            word[1] = '\0';
            word[2] = '\0';
            word[3] = '\0';
            word[4] = '\0';
            word[5] = '\0';
            word[6] = '\0';
            word[7] = '\0';
            word[8] = '\0';
            word[9] = '\0';
//          printf("\n");
//          printf("sentence position %d ",x);
           }
           else //assign the letters from sentence[] to letters in word[]
           {
            word[w] = sentence[x];
            w--;
//          printf("word length %d ",w);
//          printf("%c",sentence[x]);
           }
         }
//print the first word because im using space to delimit the words unless i have a space at the
//beginning of the sentence the code above will skip the first word inputed
    printf(" ");//print the space followed by what is in the word buffer/array
    printf("%c",word[0]);
    printf("%c",word[1]);
    printf("%c",word[2]);
    printf("%c",word[3]);
    printf("%c",word[4]);
    printf("%c",word[5]);
    printf("%c",word[6]);
    printf("%c",word[7]);
    printf("%c",word[8]);
    printf("%c",word[9]);



if ( terminator != '\0' ) //prints a . ? or ! if it is including in the inputed sentence
    printf("%c",terminator);

    printf("\n");
    printf("\n");
return 0;

我一直在考虑将单词定义为空格之间的字符序列。因此，当到达一个空格时，返回，打印每个字符，直到找到另一个空格。我的第一个版本的程序只打印了第一个单词。它的当前版本只打印其他单词。我已经被困在这两天了，所以任何帮助都是非常感谢的。这是我的代码，以及一个输出示例。希望我已经正确地记录了我的代码。提前谢谢

代码

/*包括标准I/O库*/
#包括
/*定义主要*/
内部主（空）{
/**
*声明存储句子的字符数组，以及
*表示光标下当前字符的字符，以及
*终止字符
*/
字符句子[100]={''}，c，tc；
/**
*声明循环计数器已初始化为0，增量
*变量以及所读句子的大小
*/
int i=0，j=1，size=0；
/*明白了吗*/
printf（“输入句子：\n”）；
对于（c=getchar（）；（c！='。）&&（c！='！'）&&
（c！='？'）&&（c！='\n'）；c=getchar（），i++）{
语句[i]=c；/*将当前字符存储在数组中*/
size++；/*增加句子的大小*/
}
tc=c；/*获取终止字符*/
/**
*向后遍历数组，打印每个字符序列
*空间之间
*/
对于（i=99；i>=0；i--）{
如果（句子[i]=''）{
while（句子[i+j]！=“”）{
printf（“%c”，句子[i+j]）；
j++；
}
j=1；/*重置增量变量*/
printf（“”；/*打印尾随空间*/
}
}
/**
*删除尾随空格并打印终止字符，
*还有一条新路线
*/
printf（“\b%c\n”，tc）；
返回0；/*程序成功执行时返回0*/
}

输出：

---

将每个单词推到堆栈上，然后从索引0到N-1读取堆栈

要考虑的另一种方法：

you can cage a swallow can't you?
uoy t'nac wollaws a egac nac uoy?
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
you t'nac wollaws a egac nac uoy?
^^^
you can't wollaws a egac nac uoy?
    ^^^^^
you can't swallow a egac nac uoy?
          ^^^^^^^
you can't swallow a egac nac uoy?
                  ^
you can't swallow a cage nac uoy?
                    ^^^^
you can't swallow a cage can uoy?
                         ^^^
you can't swallow a cage can you?
                             ^^^

对于每一件你想颠倒的事情（无论是一整句话还是一个词）：

找到开始和结束

交换开头和结尾字符

“向内”移动一次

一直走到“中间”

由于反转字符串块是一种常见的操作，因此将其设置为自己的函数是有意义的。由于该功能需要完成其工作的唯一信息是：

弦

起始索引

结束索引

你认为函数的参数是什么

另一个需要反复做的常见事情是“找到”某个东西，无论是空格还是标点符号。您可能需要自己编写，或者如果可以使用库函数，或者需要提示，请查阅：

man strcspn

---

这里有一个例子，可以实现我提到的。首先，反转每个单词的位置，然后反转整个字符串。下面是一个

reverse（）

函数，它使用给定的定界字符反转在位字符串。如果愿意，可以扩展为使用多个分隔符

char *reverse(char *str, char delim)
{
  char *end = strchr(str, delim);
  char *ret;
  char tmp;

  if (end == NULL)
    end = strchr(str, '\0');

  ret = end + 1;
  end--;

  while (end > str)
  {
    tmp = *str;
    *str = *end;
    *end = tmp;

    end--;
    str++;
  }

  return ret;
}

下面是一个带有一个小示例程序的用例：

int main(int argc, char **argv)
{
  char *end = strchr(argv[1], '\0');
  char *str = argv[1];

  while (str < end)
    str = reverse(str, ' ');

  reverse(argv[1], '\0');
  printf("%s\n", argv[1]);

  return 0;
}

---

我还没试过。希望能对你有所帮助

char temp[100];
int j=0, k=100, l=0;
for(i=size-1; i>=0; i--){
  if(sentence[i] == ' ' || i == 0){
    if(k-i >= 2){// at least one character

      if(i==0) j = 0;
      else j = i+1;

      for( l=0; j < k; j++, l++){
         temp[l] = sentence[j];
      }
      temp[l] = '\0';
      printf("%s ",temp);
    }
    k = i;
  }
}
printf("\b%c",tc);

chartemp[100]；
int j=0，k=100，l=0；
对于（i=size-1；i>=0；i--）{
如果（句子[i]=''| i==0）{
如果（k-i>=2）{//至少一个字符
如果（i==0）j=0；
否则j=i+1；
对于（l=0；j

int main（）
{
已发送字符[50]，最后，s；
整数i，j，长度k，温度b；
clrsc（）；
i=0；
printf（“输入一个句子：”）；
sent[i]=getchar（）；
while（sent[i]！='\n'&&sent[i]！='.&&sent[i]！='？'&&sent[i]！='.）
{
发送[++i]=getchar（）；
}
last=sent[i]；//存储最后一个字符
b=i；//字符串的长度
printf（“句子的反面：”）；
对于（；；）
{
k=b-1；//从最后一个位置开始
温度=k；
while（发送[k]！=''&&k！=-1）
k--；
s=k；//在此处存储空间
b=s；
对于（j=b+1；j这是我的答案

/*编写一个程序，将句子中的单词颠倒过来：

输入一句话：你能关一只燕子，不是吗

颠倒句子：你不能吞下笼子，是吗

提示：使用循环逐个读取字符并将其存储在一维字符数组中

让循环在句点、问号或感叹号处停止--
（“终止字符”），保存为单独的字符变量

然后使用第二个循环在数组中向后搜索最后一个单词的开头

打印最后一个单词，然后向后搜索下一个单词。
重复此操作，直到最终到达数组的开头

最后打印终止字符

*/
#include<stdio.h>

int main()
{
int ch;
char sentence[200]; //hard set a limit of 200 character sentence
char word[10] = {'\0','\0','\0','\0','\0','\0','\0','\0','\0'}; //hard set limit of 10 character words
int i = 0; //character position in input
int w = 9; //character position in word
char terminator = '\0';
printf("Enter a sentence:");
   while  ( (ch=getchar()) != '\n' )
       {
       if ( ch == '.' || ch == '?' || ch == '!')
          terminator = ch;
       else
         {
         sentence[i] = ch;
         i++;
         }
//       printf("%d",i);
       }
       sentence[i] = '\0';//set last character to null


    int x;
    for ( x=i ; x >= 0 ; x-- )
        {
           if ( sentence[x] == ' ' )
           {
            printf(" ");//print the space followed by what is in the word buffer/array
//          printf("word length %d ",w);
            printf("%c",word[0]); //probably should have a for loop here
            printf("%c",word[1]);
            printf("%c",word[2]);
            printf("%c",word[3]);
            printf("%c",word[4]);
            printf("%c",word[5]);
            printf("%c",word[6]);
            printf("%c",word[7]);
            printf("%c",word[8]);
            printf("%c",word[9]);
            w = 9 ;
            word[0] = '\0'; //fill the word buffer/array with null
            word[1] = '\0';
            word[2] = '\0';
            word[3] = '\0';
            word[4] = '\0';
            word[5] = '\0';
            word[6] = '\0';
            word[7] = '\0';
            word[8] = '\0';
            word[9] = '\0';
//          printf("\n");
//          printf("sentence position %d ",x);
           }
           else //assign the letters from sentence[] to letters in word[]
           {
            word[w] = sentence[x];
            w--;
//          printf("word length %d ",w);
//          printf("%c",sentence[x]);
           }
         }
//print the first word because im using space to delimit the words unless i have a space at the
//beginning of the sentence the code above will skip the first word inputed
    printf(" ");//print the space followed by what is in the word buffer/array
    printf("%c",word[0]);
    printf("%c",word[1]);
    printf("%c",word[2]);
    printf("%c",word[3]);
    printf("%c",word[4]);
    printf("%c",word[5]);
    printf("%c",word[6]);
    printf("%c",word[7]);
    printf("%c",word[8]);
    printf("%c",word[9]);



if ( terminator != '\0' ) //prints a . ? or ! if it is including in the inputed sentence
    printf("%c",terminator);

    printf("\n");
    printf("\n");
return 0;

*/
#包括
int main（）
{
int-ch；
字符句子[200]；//硬设置200字符句子的限制
字符字[10]
char temp[100];
int j=0, k=100, l=0;
for(i=size-1; i>=0; i--){
  if(sentence[i] == ' ' || i == 0){
    if(k-i >= 2){// at least one character

      if(i==0) j = 0;
      else j = i+1;

      for( l=0; j < k; j++, l++){
         temp[l] = sentence[j];
      }
      temp[l] = '\0';
      printf("%s ",temp);
    }
    k = i;
  }
}
printf("\b%c",tc);

int main()
{

    char sent[50],last,s;
    int i,j,length,k,temp,b;
    clrscr();
    i=0;
    printf("Enter a sentence: ");
    sent[i]=getchar();
    while(sent[i]!='\n'&&sent[i]!='.'&&sent[i]!='?'&&sent[i]!='!')
    {
        sent[++i]=getchar();
    }
    last=sent[i];//storing last char
    b=i; //length of string
    printf("Reverse of sentence: ");
    for(;;)
    {
        k=b-1;// begin from last position
        temp=k;
        while(sent[k]!=' ' && k!=-1)
        k--;
        s=k;//storing space here
        b=s;
        for(j=b+1;j<=temp;j++)
        putchar(sent[j]);
        if(s!=-1)
        putchar(sent[s]);
        if(b==-1)
        break;
    }
    putchar(last);
    getch();
    return 0;
}

*/
#include<stdio.h>

int main()
{
int ch;
char sentence[200]; //hard set a limit of 200 character sentence
char word[10] = {'\0','\0','\0','\0','\0','\0','\0','\0','\0'}; //hard set limit of 10 character words
int i = 0; //character position in input
int w = 9; //character position in word
char terminator = '\0';
printf("Enter a sentence:");
   while  ( (ch=getchar()) != '\n' )
       {
       if ( ch == '.' || ch == '?' || ch == '!')
          terminator = ch;
       else
         {
         sentence[i] = ch;
         i++;
         }
//       printf("%d",i);
       }
       sentence[i] = '\0';//set last character to null


    int x;
    for ( x=i ; x >= 0 ; x-- )
        {
           if ( sentence[x] == ' ' )
           {
            printf(" ");//print the space followed by what is in the word buffer/array
//          printf("word length %d ",w);
            printf("%c",word[0]); //probably should have a for loop here
            printf("%c",word[1]);
            printf("%c",word[2]);
            printf("%c",word[3]);
            printf("%c",word[4]);
            printf("%c",word[5]);
            printf("%c",word[6]);
            printf("%c",word[7]);
            printf("%c",word[8]);
            printf("%c",word[9]);
            w = 9 ;
            word[0] = '\0'; //fill the word buffer/array with null
            word[1] = '\0';
            word[2] = '\0';
            word[3] = '\0';
            word[4] = '\0';
            word[5] = '\0';
            word[6] = '\0';
            word[7] = '\0';
            word[8] = '\0';
            word[9] = '\0';
//          printf("\n");
//          printf("sentence position %d ",x);
           }
           else //assign the letters from sentence[] to letters in word[]
           {
            word[w] = sentence[x];
            w--;
//          printf("word length %d ",w);
//          printf("%c",sentence[x]);
           }
         }
//print the first word because im using space to delimit the words unless i have a space at the
//beginning of the sentence the code above will skip the first word inputed
    printf(" ");//print the space followed by what is in the word buffer/array
    printf("%c",word[0]);
    printf("%c",word[1]);
    printf("%c",word[2]);
    printf("%c",word[3]);
    printf("%c",word[4]);
    printf("%c",word[5]);
    printf("%c",word[6]);
    printf("%c",word[7]);
    printf("%c",word[8]);
    printf("%c",word[9]);



if ( terminator != '\0' ) //prints a . ? or ! if it is including in the inputed sentence
    printf("%c",terminator);

    printf("\n");
    printf("\n");
return 0;

  using System;

  namespace SampleString
  {
    class ReverseWordsInSetence
    {
        // Reverse words in a string (words are separated by one or more spaces).
        private static String GetReverseWordsInSetence(string sentence)
        {
            char[] stringArray = sentence.ToCharArray();
            int len = sentence.Length;
            int startIndex = 0;

            Swap(ref stringArray, ref startIndex , len-1);
            startIndex = 0;

            for (int currentIndex = 0; currentIndex < len; currentIndex++)
            { 
                if (stringArray[currentIndex].Equals(' '))
                {
                    Swap(ref stringArray, ref startIndex, currentIndex-1);
                }
                else if (currentIndex == len - 1)
                {
                    Swap(ref stringArray, ref startIndex, currentIndex);
                }

            }

            return new string(stringArray);
        }


        private static void Swap(ref char[] a, ref int i, int j)
        {
            int tempIndex = j;

            while (i < j)
            {
                if (a[j].Equals('.'))
                {
                    j--;
                }
                else
                {
                    a[i] ^= a[j];
                    a[j] ^= a[i];
                    a[i++] ^= a[j--];
                }
            }

            i = tempIndex + 2;
        }

        static void Main(string[] args)
        {        
           Console.WriteLine(GetReverseWordsInSetence("Hello World."));
           Console.ReadLine();
        }
    }
}

 void reverse(char s[],int start,int stop){
 char t;
 while(start<stop){
    t = s[start];
    s[start]=s[stop];
    s[stop]=t;
    start++;
    stop--;
}
}

int main() {

char str[100];
gets(str);

int pos=0,begin=0,end;
reverse(str,begin,strlen(str)-1); //since the last character is null

while(pos<=strlen(str)){
    if((str[pos]==' ')||(str[pos]=='\0')||(str[pos]=='?')||(str[pos]=='!')){
        end = pos - 1; 
       reverse(str,begin,end);  
        begin = pos+1; //for the next word
    }

    pos++;

}   

cout<<str;
return 0;
}

#include <stdlib.h>

int main()
{
char s[20][20];
int i=0,length=-1;
for(i=0;;i++)
{
    scanf("%s",s[i]);
    length++;
    if(getchar()=='\n')
        break;
}
for(i=length;i>=0;i--)
    printf("%s ",s[i]);
return 0;
}

/* Outer loop goes backwards through the array, effectively reversing the sentence */
for(i = 99; i >= 0; i--) {

    if(sentence[i] == ' ') {

        /* Inner loop goes forward, reversing the word again */
        while(sentence[i + j] != ' ') {

            printf("%c", sentence[i + j]);
            j++;
        }

        j = 1;
        printf(" ");
    }
}

/* ... */
char sentence[100] = { ' ' }, c, tc;

/* ... */
int i = 0, j = 1, size = 0;

/* Get the sentence */
printf("Enter a sentence: \n");
for(c = getchar(); (c != '.') && (c != '!') && 
    (c != '?') && (c != '\n'); c = getchar(), i++) {

    sentence[i] = c; /* Store the current character in the array */
    size++; /* Increase the sentence's size */
}

Enter a sentence:
 you can cage a swallow can't you?
you can't swallow a cage can you?

/**
 * Declare a loop counter already initialized at 1, an incremental
 * variable, as well as the size of the read sentence
 */
int i = 1, j = 1, size = 0;

/**
 * Go backward through the array, printing each sequence of characters
 * between spaces
 */
for(i = 99; i >= 0; i--) {

    if(sentence[i] == ' ') {

        while(sentence[i + j] != ' ') {

            printf("%c", sentence[i + j]);
            j++;
        }

        j = 1; /* Reset the incremental variable */
        printf(" "); /* Print a tailing space */
    }
}

/* print the last word */
while(sentence[i + j] != ' ') {

    printf("%c", sentence[i + j]);
    j++;
}

#include<stdio.h>

void print_word(char[] sentence, int i) {
    int j = 1;
    while(sentence[i + j] != ' ') {
        printf("%c", sentence[i + j]);
        j++;
    }
}

int main(void) {
    char sentence[100] = { ' ' }, c, tc;
    int i = 0, j = 1, size = 0;
    printf("Enter a sentence: \n");
    for(c = getchar(); (c != '.') && (c != '!') && 
        (c != '?') && (c != '\n'); c = getchar(), i++) {
        sentence[i] = c; /* Store the current character in the array */
        size++; /* Increase the sentence's size */
    }
    tc = c; /* Get the terminating character */
    for(i = 99; i >= 0; i--) {
        if(sentence[i] == ' ') {
            print_word(sentence, i);
            printf(" "); /* Print a tailing space */
        }
    }
    print_word(sentence, i);
    printf("\b%c\n", tc);
    return 0; /* Return 0 upon successful program execution */
}